"Expected an Indented Block" Error, but there is an indented Block

try:

#Game loop:
while True: #The error is occurring here
    load()
    #Main game loop:
    while game_over == False:
        load_stage()
    #Win screen and restart option:
    print('\n**********************************************')
    print ('Congratulations! You Won!')
    answer = input('Would you like to restart?\nIf so type \'restart\'.')
    if answer == 'restart':
        restart()
        save()
   

The Error arise'd due to inconsistency in indentation, meaning that your program didn't had a consistent indentation scheme. In general it is advised to use 4 space's (where space = single spacebar) to represent an indented block.

Inconsistency can also arise, if your program uses Tab and spaces interchangeably, for indentation.